Means for grading articles by size



1953 s. BALLARD, JR., ET AL 2,661,840

MEANS FOR GRADING ARTICLES BY SIZE Filed Sept.' 10, 1951 6 Sheets-Sheet l Dec. 8, 1953 S. BALLARD, JR., ET AL Filed Sept. 10, 1951 6 Sheets-Sheet 2 FIG.3.

l i i 45 g I 1a i k\\\ IA \\I I I T I 41 3'4 36 i J E i i l I i l Filed Sept. 10, 1951 1953 s. BALLARD, JR, ET AL 2,661,840

MEANS FOR GRADING ARTICLES BY- SIZE 6 Sheets-Sheet 3 .f/EPHEN Jar/0R Pen-w IVA-wow ATTORNEY Filed Sept. '10, 1951 Dec. 8, 1953 SVBALLARD, JR, 'ETAL 2,

- MEANS FOR GRADING ARTICLES BY SIZE 6 Sheets-Sheet 4 4 FIG. 6

Ltd/M7045: STEPHEA/iuMMZ/MM IPEIER ye/vow MF/L m Dec. 8, 1953 s. BALLARD, JR, ET AL I 2,66

MEANS FOR GRADING ARTICLES BY SIZE Filed Sept. 10, 1951 6 Sheets-Sheet 5 [wen/ran s .gr-ramvey 1953 s. BALLAl RD, JR, ET AL 2,661,840

MEANS FOR GRADING ARTICLES BY SIZE Filed Sept. 10, 1951 6 Sheets-Sheet 6 FIGS.

STEM/Jim [mm PETER 2am? Patented Dec. 8, 1953 MEANS FORGRADING ARTICLES BY SIZE I Stephen Ballard, Jr., and Peter Renold, Colwa-ll, Malv-ern, England Application September 10, 1951, Serial No. 245,782

This invention relates to new or improved means for grading articles by size.

The invention is concerned with a machine which is primarily intended for grading fruit such as apples, plums, and tomatoes but is applicable to the grading of any other articles of spherical, ovoid, or similar outline.

According to our invention a machine for grading articles by size comprises a conveyor in which transverse bars or rollers are carried at their ends byor form the connecting pivots of alternate links of travelling chains and means are provided for progressively varying the spacing between adjacent bars or rollers by movement of the intermediate pivots of the chain links into and out of the normal plane of the chain. When all the pivots of the chain links are in the same plane the spacing between the bars or rollers is at a maximum and the spacing can be progressively reduced by moving the intermediate pivots of the links out of that plane so that adjacent links are inclined to each other at a progressively greater angle, the link pivots which carry the bars or rollers being guided in or on straight tracks in the usual manner while the intermediate pivots carryrollers co-operating with separate inclined guides or ramps and are free to move into and out of the plane of the guided link pivots. l The chains are carried over sprockets at each end of the conveyor in the usual way, one or both of the sprockets being driven, and as the total effective length of each chain will remain constant and the links will be at their maximum spacing when passing over the sprockets the driv ing of the chains presents no difiiculty. Articles to he grade will be fed on to the conveyor at a point where the spacing between the 4 Claims. (01. 209-106) bars or rollers is at a minimum, and as the articles are carried along the spacing increases progressively so that articles of progressively increasing size will drop through between the bars or rollers, the articles of difierent sizes being re ceived by separate shoots, trays, conveyor belts or other receptacles below the grading conveyor. The movement of the intermediate link pivots into and out of the plane of the chain can be effected in various ways. 1

Usually the guides or tracks for the movable link pivots will be so arranged that the spacing between the bars or rollers of the conveyor will be rapidly reduced to a minimum after the chains come off the sprockets at the feeding end of the conveyor and the articles to be graded will be fed on to the conveyor at or immediately after-the point of minimum spacing. The spacing will then be gradually increased and will reach its maximum before the chains pass on to the sprockets at the other end.

Two practical means for carrying our invention into effect and some modifications are illustrated diagrammatically in the accompanying drawings in which- Figure 1 is a side elevation of a chain showing two pairs of links with one intermediate pivot in its normal position and the other depressed.

Figure 2 is a fragmentary end elevation of a portion of the chain and guides.

Figure 3 is an elevation in part section showing the mounting and arrangement of the rollers.

Figure 4 is a plan of a portion of a, grading machine employing shaped members on the rolle'rs to define openings for the articles to be separated.

, Figure 5 is a side elevation of the rollers shown in Figure 4.

Figure 6 is a side elevation of a complete machine.

Figure 7 is a plan view, and

Figure 8 is an end elevation viewed from the loading end of the same machine.

Figure 1 shows diagrammatically in side eleva 1 tion a portion of a chain forming one side of a conveyor for the articles tobe graded. The conveyor is formed by parallel rollers l0, ll, l2 ro-' 1 tatably mounted on spindles ID IH, 12 of which the ends are fixed in or extend through alternate hollow pivots l3, l4, [5 connecting the links of the chain. .The rollers are guided to travel in a'horizontal plane so that the pivots I3, l 4, l5 also travel in a horizontal plane. Alternate links l6, ll, I8 of the chain areof normal shape but the intermediate links I9, 20 are'triangular in shape with two link pivots on the base side which are shown as being spaced at the same distance apart as the pivots of the adjacent plain; links but may be spaced at any convenient pitch;

The triangular link is carries the pivot'ld of the roller l l and an independent pivot 2| connecting it to the plain link It. The triangular link, 29 carries the pivot l5 of the roller l2 and anindependent pivot 22 connecting it to the plain link H. The apex of each triangular link carries a roller 23 which is normally elevated above the plane of the chain, and thebase of each triangular link normally is in alignment with the lower edge of the adjacent plain links,

all the link pivots being in the same horizontal of one end of one;

rollers l and H carried by the pivots at other ends of the plain an d triangular links. Thus the normal spacing between adjacent'rollers is reduced by an amount dependent on -the ex tent to which the roller 23 is depressed; as-wiilfbes I appreciated by a comparison of thespacing be; tween the rollers 10 and I I with that between the rollers H and I2.

For the purposes of illustration the guide 25 is bewnsteeuly inclined but me radi a a hine the. n inationw llbe ver -small o tha hem sresslrechangeinthespacinaoi the rollers om. a minimum to a maximum will occupysthemajor art. o the l n h. i the conveyor nd al w lenty. of; ere far he s parate shoots. tr ys. or otherr centa lesier. graded articles of. difier n sizes.

Ina .p eierred ay nt the ov heaclguides with which the. olle 11. th ria gular inlsss n the ins. enga e wil be arran ed to reduce the spa i sbetw en h grading rollersto a. min mum immediately a t r he hains ave, the nr k ts ateneens id 'the onv yor. t mainta n thev minimum spacin fa pl'edetermineddis: tance, and-then to increase the spacing gradually u to th ax m m.

A ic e o e se arat d ar fedo totbecenv y r 11 s in a l fi' he pinta which. he

roller spacing has been reduced to a minirnun and over the partof the conveyor wherethe minimum spacing is maintainedany stalks leaves, or, other foreign matter together with any very small articles will-drop through. Then as the articles are carried on by the conveyor over the part where the spacing between the: rollers is graduallyincreasing the articles willbe graded according to size and delivered-intodifferenttraysor shoots below the conveyor.

The grading rollersare conveniently arranged to roll adjacent-eachend on horizontal tracks asshownldiagrammatieally at 25 in Figure 2. In that figure-26 is oneof-the: grading rollers, 21 are plain-.linksoft-he chain; 28 are triangular links, andiZSris-theoverhead track co-operating with the rollers 30: on=thetriangularlinks.

The-rollers arepreferably mounted" on. ball or rollen bearings. ontheir spindles to reduce to a minimum the power required to drive the conveyor.

Figure 3" shows; a: practical arrangement in which. the roller is formed-by atube 3-! mounted tolrotate at: eachend on needl'e roller bearings working between a thin liner 33' in the sleeve and a; bush 34lon1thespindle: 35. The bush: and bearing rollers are located'inone-direction by a disc d izbackedby a.flangedboss 31 and in the other;by;-a flanged disc= 38: co-operating with a bell thrustcbearing. 39: arranged" between the disc nd'a r nternalz leeve 49 inthe tube. A spacin sleeve 41: is. mounted on the spindle between the disc {l1} and; a complementary disc at; the. other end-eithe n nd The:- nd f. the ler. 1 a. hor zontal uide lila d he ria ula nk -Q1 he. hain co-operate with an overhead guide 43, the guides being mounted on angle-section members M, 45 forming part of the fixed frame of the conveyor. The part of the roller between the guides may 0 be covered with a rubber sleeve 46 to prevent damage to the fruit or other articles being graded.

Alternatively, as shown in Figures 4 and 5 there maybe mounted5 on the; rollers axially: spaced members 47, 481 of suitable material: such as moulded rubber each having the form of a short cylinder with a. frustum of a cone on both ends 011 On one endin, the case of the members at the ends of the rollers. When these members are 1 5- mounted on; the; rollers in axially spaced relationship their conical faces co-operate with those of the adjacent members and of the members on the next roller to define openings of substantiallyrsduare outline in plan.

The effective size of these openings is varied by. the variationin the spacing of: the rollers as the conveyor travelsjalong. This is-clearly.shownv in. Eigure 4, where threercllersareillustratedin planwith the spacing between two .of. them at its. minimum. andthe spacing between the other two.

at its. maximum- The other parts: of, the'mechanism shown in Figuresrhandfi. have been given the same refern en meral as thecorrespondin :p -11 4 ure 2 i ures 6,.7 ands show the mode of per tion o a. preferr dv orm. ff the. complete.- machine. The fruit or. other articles tobe graded. are. car.- esib th e. .d conv y r 4. 111 to the graderv acl1ain 511., Thedeedtconveyor 43. adjustablein. e ght from the position-shownintfiigure e .upto

the horizontal, pivotingabout. the spindle. 5.4;

Ear. the firstpa t. of. its horizontal. trav l he;

grader: chain 5 0 ,-is,elosedupltoits minimum space. ns. and on y; the.-sn.1a11est:artic1es-, such, as twigs, leaves. and otherforeign; matter; fall through. on

t a: r ss-be t 52-. amaze-ca ie aside-1 yond.

the r m-be t. 52 t e g ader. chain. Ells: prosresa si-ve y; en n sb. out bythe 1 acti n ofhe' overhead:

4e uide: net-shown fi re 6i nd the articl fall, in: graded sizes a described above on. to. a cend tres -b lt at; be ng. thenc carried t hu es. 9. e h rolle tin devi es'fi alone-- e of the grader; chain andzover-theybottom run, A.

5 5 k v mn qprive from laysha-ft 51-, istaken through11'e du ti n s ban fiasandas f ety d sl t h. 59* to:

the maingrader chain BB-andthe feed conveyor Wiaspindles at and: 5 l respectively Weda m 60' sma king-for sraflinaart eles by s z ma s nszaconv rter onsisting itw pafiedip le1..dr-. err; 31ains a hiormed by-links of n0rm il:v contour: al er ating with rian ar l nk llfiqefi nivetsxon he-base; of each, of said; triangular; connecting it to; the ends oradi acent links; a rpllen at the: apexpft each: trin ular' link having? its agis spaced from a;plane;- containing; the axes of the base pivots,- transverse conveyingmen bers; extending between the chains and. car- TC- riedbyaalternate link pivots; means forconstrainingsaid-alternate link-pivots to movein a. com.- mon; planeover-a part of; their travel; and guides inclined to; saidzcommon plane co-operatingwith aidr rnllers; for; moving said-; triangular links a n-r. gularlspaboutgthfi. altfilnate link pivots: and mov.-.

ing the intermediate link pivots out of and into said common plane.

2. A machine for grading articles by size comprising a chain conveyor having parallel conveying members extending transversely between parallel driven chains, each of said chains comprising plain links alternating with intermediate links of triangular outline, spaced pivots in the base of each triangular link to which said plain links are connected, one end of each conveying member carrying one of said base pivots of each triangular intermediate link, a roller at the apex of each of said intermediate links, means for constraining the conveying members to'travel in a common plane over the operative part of the conveyor, and guides inclined with respect to said plane cooperating with said rollers on the intermediate links for moving said intermediate links angularly about said base pivots carrying the conveying members and controlling the displacement of the other base pivots out of said plane to vary the spacing between the conveying members progressively along a portion of the operative part of the conveyor.

3. A machine for grading articles by size according to claim 2 wherein said conveyor members comprise rollers mounted to rotate on antifriction bearings on spindles, the ends of said spindles forming chain link pivots.

4. A machine for grading articles by size according to claim 2 wherein said conveyor members comprise rollers carrying axially spaced members of resilient material each of said members having the form of a short cylinder with a frustum of a cone on each end and the conical faces of said members cooperating with those of the adjacent members and of the members on the next roller to define openings of substantially square outline in plan.

STEPHEN BALLARD, JR. PETER RENOLD.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,489,585 Tinklepaugh Apr. 8, 1924 2,335,164 Wayland Nov. 23, 1943 FOREIGN PATENTS Number Country Date 423,149 Great Britain Jan. 25, 1935 

